From an evolutionary point of view, there is a lot left to be said about love, according to Professor of Evolutionary Psychology Mark van Vugt. „Love goes beyond romance. We are hard-wired to be the most monogamous of all simian species. As a rule, we’re looking for a single romantic partner to spend our lives with.”

Is love a popular topic within evolutionary psychology? 

„Without love, our field would cease to exist. Reproductive success is the most important condition for having children, and people who loved each other were most successful in raising a family and spreading their genes. Love plays a key role in passing on your genes to the next generation."

So the idea of a happy family is entirely justified from an evolutionary point of view?

„Absolutely. We are the most monogamous of all simian species. Humans go looking for a single romantic partner to spend our lives with, or at least the part of our lives that we have a family and raise children together. That’s simply how we are wired. Nurturing a helpless baby into a full-grown adult who can start their own family requires major investments and sacrifices."

„Just because we are the most monogamous species in our infraorder doesn’t mean that we’re exclusively monogamous. In some senses, men and women even have conflicting interests. Men do not have to invest as much in their offspring, as they cannot carry or nurse children, and they may explore other relationships to increase their chance of procreating during this time. Men generally have a higher sex drive and are slightly more likely to seek short-term relationships, which can prompt them to pay for sex, engage in adultery, pursue extramarital affairs, or seek a divorce."

Why do people fall in love? 

„People generally tend to look for a compatible partner, driven by the fact that we are so innately monogamous. The notion that opposites attract is entirely false. We are assortative maters, which means that we are most likely to find a partner in our own network - someone who shares the same interests, background and education. After all, partners from a similar background are most likely to agree on how to shape family life and raise a child. If you are looking for a successful long-term relationship, my advice would be to look at the people around you, rather than going further afield."

And what about physical appearance and smell? 

„Physical attractiveness and youthfulness are more important in women, while men have to be ambitious, intelligent, or self-sufficient. Both sexes also prioritise kindness, a good character and reliability, which are all valuable ingredients in a long-term relationship."

„Scent goes beyond smelling good. In a scent study, sociologists observed that women were more likely to prefer the T-shirt of a man with more masculine characteristics. This boils down to the relationship between scent and gene compatibility: you are sexually repelled by the smell of a sex partner who is "too genetically similar” to you to avoid inbreeding."

Is a shift taking place in how we view love and sexuality?

„Women tend to naturally look for a successful, high-status partner, and although they are becoming more financially independent and highly educated, this instinct has not changed. Women refuse to date down, which effectively restricts their dating pool, especially in cities like Amsterdam that are home to relatively many highly educated single women and few highly educated single men."

„One of my Chinese PhD students once called herself "the third gender”, distancing herself from the traditional man-woman paradigm. She saw herself as a highly-educated woman who would struggle to find a husband in China, should she return. In certain parts of the world, including in rural areas in the Netherlands, many men who occupy a somewhat lower social stratum may struggle to find a wife. For these men, it becomes an option to look for a bride overseas, and I know - from anecdotal evidence - that there are men who do just that."

In your book Lucy, Darwin and lady Gaga, you write that research in humans and animals shows how skewed sex ratios can affect society in unexpected ways. 

„When it comes to love, the sex ratio, the distribution of men and women in a population, influences the strategy men and women choose to get a partner. Researchers have generally found that women are pickier and that men have to adapt when they outnumber women, becoming more faithful and loyal to show their suitability as a long-term partner."

„What’s more, there will necessarily be a group of young men who struggle to find a wife. A skewed sex ratio - with men outnumbering women - also has a disruptive effect on society. Men start to compete with each other, exhibit criminal behaviour and may even start killing each other in order to boost their status for that small group of women. In board rooms dominated by men, they tend to compete with each other. Because they need status to find a partner, it is in their interest to be the alpha male. We are only now starting to investigate how team dynamics change in board rooms with a more evenly balanced sex ratio. You would expect power relations to change and for a more egalitarian status quo to emerge, but who is to say that the women won’t find another way to eliminate their rivals?"

How big is the chance that you will find the one at VU Amsterdam? 

„In Amsterdam and many other university cities, there are three young women for every young man, giving men the upper hand. Young women will have to lower their standards in order to find a partner, resulting in more short-term sexual relationships. Research shows that in a population where there are more young women relative to young men, women tend to choose to invest in their careers and put their desire to have children on hold."

Is there a way to harness these insights? Do you have a killer tip for finding a partner?

„One of the main features that people look for in a long-term partner is a sense of humour. Every relationship will hit choppy waters at some point, and having something to laugh about together can be a life-saver. We studied what kind of humour women like in men and learned that young women looking for a date were most drawn by men who ridiculed others and came off well themselves, while self-deprecating humour was the least popular. And it’s a cliché for a reason: men are mainly interested in women who will laugh at their jokes."

Some of the conclusions you draw chafe with the current debate around gender equality.  

„That may be true, and I am very aware that these are sensitive issues, but my conclusions are based on scientific research performed all over the world. The findings say something about how the average man differs from the average woman in terms of what they prioritise in relationships - the goal is not to make sweeping generalisations. Sure, you can examine the differences between men and women from a feminist or philosophical perspective, but you will also encounter numerous bizarre, unfounded claims about human nature. Evolutionary psychology is unburdened by such claims and has a much larger scope."

„Take watching porn, for instance, which men are - on average - much more likely to do than women. It is often accompanied by a sense of shame, as if it were a sin, but the evolutionary psychologist in me can explain exactly why it’s so popular among men. After all, men simply have a higher sex drive than women and are more geared towards short-term sex. Watching porn is a way to channel that in a way that does not cause too much harm to society. Research shows that male fans flock to porn sites after a football match, with traffic increasing by 40%. They probably produced a lot of testosterone during the match, a hormone you need when you go into battle, and in the animal kingdom, the man that emerges victorious gains access to sex."

In conclusion: do you believe that evolution offers a full explanation of human behaviour (and your own), and what are your thoughts on free will?

„I don’t spend much time thinking about whether free will exists, because it’s impossible to prove either way. I will, however, briefly wear the philosopher’s hat and say that it is important for society to have the illusion of free will, as it enables us to hold each other accountable and uphold law and order. Without the illusion of free will, you’d have no reason to get out of bed in the morning."